"They're like cattle dogs with sheep – sometimes sheep stray to another paddock. Well, the cattle dog is going to bark and sometimes bite," he said.

Mr Turnbull, the opposition's communications spokesman, has attracted the ire of colleagues in the past week by criticising the coalition's climate change policy and signalling he would like to return to the leadership in the future.

Related Quotes

Company Profile

"There's a lot of bromance in the coalition at the moment and that bromance is based on the fact that we respect each other and stand up for each other," Mr Hockey told the Seven Network.

Labor frontbencher Tony Burke said there was no question the critical email was aimed at taking Mr Turnbull down a peg.

"They either work together or they can't work together and he (Mr Abbott) gets rid of him," Mr Burke told the Seven Network.

Meanwhile, Fairfax media has reported that senior Liberal senator Nick Minchin clashed with Mr Abbott on Tuesday over a government bill to increase the excise on alternative fuels.

Senator Minchin argued in the coalition party room that the excise increase was a Howard government policy and a good policy, but Mr Abbott said times had changed and the cost of living was an issue the coalition was pursuing.

Mr Abbott reportedly told Senator Minchin that faced with a choice between "policy purity and pragmatic political pragmatism, I'll take pragmatism every time".